Patents by Inventor J.K. Leong

J.K. Leong has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11703460
    Abstract: Methods and systems for detecting and classifying defects based on the phase of dark field scattering from a sample are described herein. In some embodiments, throughput is increased by detecting and classifying defects with the same optical system. In one aspect, a defect is classified based on the measured relative phase of scattered light collected from at least two spatially distinct locations in the collection pupil. The phase difference, if any, between the light transmitted through any two spatially distinct locations at the pupil plane is determined from the positions of the interference fringes in the imaging plane. The measured phase difference is indicative of the material composition of the measured sample. In another aspect, an inspection system includes a programmable pupil aperture device configured to sample the pupil at different, programmable locations in the collection pupil.
    Type: Grant
    Filed: June 26, 2020
    Date of Patent: July 18, 2023
    Assignee: KLA Corporation
    Inventors: Zhiwei Xu, Kurt Haller, J. K. Leong, Christian Wolters
  • Publication number: 20210010949
    Abstract: Methods and systems for detecting and classifying defects based on the phase of dark field scattering from a sample are described herein. In some embodiments, throughput is increased by detecting and classifying defects with the same optical system. In one aspect, a defect is classified based on the measured relative phase of scattered light collected from at least two spatially distinct locations in the collection pupil. The phase difference, if any, between the light transmitted through any two spatially distinct locations at the pupil plane is determined from the positions of the interference fringes in the imaging plane. The measured phase difference is indicative of the material composition of the measured sample. In another aspect, an inspection system includes a programmable pupil aperture device configured to sample the pupil at different, programmable locations in the collection pupil.
    Type: Application
    Filed: June 26, 2020
    Publication date: January 14, 2021
    Inventors: Zhiwei Xu, Kurt Haller, J.K. Leong, Christian Wolters
  • Patent number: 10670537
    Abstract: A inspection system includes an illumination source to generate an illumination beam, focusing elements to direct the illumination beam to a sample, a detector, collection elements configured to direct radiation emanating from the sample to the detector, a detection mode control device to image the sample in two or more detection modes such that the detector generates two or more collection signals based on the two or more detection modes, and a controller. Radiation emanating from the sample includes at least radiation specularly reflected by the sample and radiation scattered by the sample. The controller determines defect scattering characteristics associated with radiation scattered by defects on the sample based on the two or more collection signals. The controller also classifies the one or more particles according to a set of predetermined defect classifications based on the one or more defect scattering characteristics.
    Type: Grant
    Filed: March 18, 2019
    Date of Patent: June 2, 2020
    Assignee: KLA-Tencor Corporation
    Inventors: Guoheng Zhao, J. K. Leong, Michael Kirk
  • Publication number: 20190212277
    Abstract: A inspection system includes an illumination source to generate an illumination beam, focusing elements to direct the illumination beam to a sample, a detector, collection elements configured to direct radiation emanating from the sample to the detector, a detection mode control device to image the sample in two or more detection modes such that the detector generates two or more collection signals based on the two or more detection modes, and a controller. Radiation emanating from the sample includes at least radiation specularly reflected by the sample and radiation scattered by the sample. The controller determines defect scattering characteristics associated with radiation scattered by defects on the sample based on the two or more collection signals. The controller also classifies the one or more particles according to a set of predetermined defect classifications based on the one or more defect scattering characteristics.
    Type: Application
    Filed: March 18, 2019
    Publication date: July 11, 2019
    Inventors: Guoheng Zhao, J.K. Leong, Michael Kirk
  • Patent number: 10234402
    Abstract: A inspection system includes an illumination source to generate an illumination beam, focusing elements to direct the illumination beam to a sample, a detector, collection elements configured to direct radiation emanating from the sample to the detector, a detection mode control device to image the sample in two or more detection modes such that the detector generates two or more collection signals based on the two or more detection modes, and a controller. Radiation emanating from the sample includes at least radiation specularly reflected by the sample and radiation scattered by the sample. The controller determines defect scattering characteristics associated with radiation scattered by defects on the sample based on the two or more collection signals. The controller also classifies the one or more particles according to a set of predetermined defect classifications based on the one or more defect scattering characteristics.
    Type: Grant
    Filed: April 5, 2017
    Date of Patent: March 19, 2019
    Assignee: KLA-Tencor Corporation
    Inventors: Guoheng Zhao, J. K. Leong, Michael Kirk
  • Publication number: 20180188188
    Abstract: A inspection system includes an illumination source to generate an illumination beam, focusing elements to direct the illumination beam to a sample, a detector, collection elements configured to direct radiation emanating from the sample to the detector, a detection mode control device to image the sample in two or more detection modes such that the detector generates two or more collection signals based on the two or more detection modes, and a controller. Radiation emanating from the sample includes at least radiation specularly reflected by the sample and radiation scattered by the sample. The controller determines defect scattering characteristics associated with radiation scattered by defects on the sample based on the two or more collection signals. The controller also classifies the one or more particles according to a set of predetermined defect classifications based on the one or more defect scattering characteristics.
    Type: Application
    Filed: April 5, 2017
    Publication date: July 5, 2018
    Inventors: Guoheng Zhao, J.K. Leong, Michael Kirk